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arXiv · 0901.2087

Dancing Volvox: Hydrodynamic Bound States of Swimming Algae

Knut Drescher·Kyriacos C. Leptos·Idan Tuval·Takuji Ishikawa·Timothy J. Pedley·Raymond E. Goldstein
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Abstract

The spherical alga Volvox swims by means of flagella on thousands of surface somatic cells. This geometry and its large size make it a model organism for studying the fluid dynamics of multicellularity. Remarkably, when two nearby Volvox swim close to a solid surface, they attract one another and can form stable bound states in which they "waltz" or "minuet" around each other. A surface-mediated hydrodynamic attraction combined with lubrication forces between spinning, bottom-heavy Volvox explains the formation, stability and dynamics of the bound states. These phenomena are suggested to underlie observed clustering of Volvox at surfaces.

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Knut Drescher, Kyriacos C. Leptos, Idan Tuval, Takuji Ishikawa, Timothy J. Pedley, Raymond E. Goldstein. 2009-01-14. Dancing Volvox: Hydrodynamic Bound States of Swimming Algae. https://doi.org/10.1103/physrevlett.102.168101

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